Liner for the jaw faces of pipe wrenches



y 5, 1953 E. VERGNANI ETAL LINER FOR THE JAW FACES 0F PIPE WRENCHES Filed March 19. 1952 www" Zia/ aw Way a 1%):

Patented May 5, 1953 LINER FOR THE JAW FACES OF PIPE WRENCHES Evo Vergnani, Stanley E. Vergnani, and Milton H. Vergnani, Somerville, Mass, assignors to Somerset Machine & Tool 00., Inc, Boston, Mass, a corporation of Massachusetts Application March 19, 1952, Serial No. 277,382

2 Claims.

This invention relates to improvements in wrenches of the type designed to grip pipes firmly without marring them, and more particularly to wrenches having a toggle linkage operated by two pivoted handles which swing toward each other to close the jaws. The jaws have opposed semi-cylindrical cavities arranged to embrace a pipe, the cavities being lined with semi-cylindrical liners of soft metal such as copper, brass or the like which bear directly on the pipe gripped by the wrench. The pipe can thus be gripped very strongly without marring the surface thereof. According to the invention, the two lining members of soft metal are loosely connected by tie means which permit limited movement toward and from each other but maintain them loosely assembled when dismounted from the jaws of the wrench.

Another object of the invention is to provide a tripping member on one of the handles which can be operated by a finger of the hand holding the wrench to force the two handles away from each other and thus to break the toggle so as to move the jaws apart and releasethe pipe gripped thereby. For this purpose a small lever or trigger is pivotally mounted near the end of one of the handles and can be cperated by a finger of the hand holding the wrench to press against the other handle so as to push the handles apart without shifting the hand holding the wrench or using the other hand which may be otherwise employed at the time.

For a more complete understanding of the invention reference may be had to the following description thereof of which Figure 1 is an elevation of a wrench embodying the invention;

Figure 2 is a perspective view of lining members for the wrench jaws;

Figure 3 is a section on line 3-3 of Figure 1;

Figure 4 is a section on the line l-fl of Figure 3;

Figure 5 is a fragmentary edge view of the lower portion of the wrench shown in Figure 1;

Figure 6 is a fragmentary side elevation of the lower part of the wrench shown in Figure l, the handles bein separated; and

Figure '7 is a fragmentary side elevation of the wrench showing a modified form of trigger.

The wrench thus illustrated in Figure 1 comprises two levers lll and E2 which are pivoted to each other as at M, the portions of the levers below the pivot point being adapted to serve as handles for the wrench. The lever lil has an elongated extension l6 above the pivot this extension terminating in one of the wrench jaws Ill. The opposing jaw 28 is pivoted as at 22 to the lever extension iii. The jaws l8 and 2t each have a semi-cylindrical recess containing the lining members 2% and 25 of soft metal such as brass which engagea pipe to be gripped by the wrench, the soft metal being capable of firmly gripping the pipe without marring the surface thereof.

The semi-cylindrical linin members 24 and 26 together almost constitute a complete hollow cylinder as illustrated in Figure 2, suitable clearances 39 and 32 being left between the members. The lining members are constructed to grip a given size of pipe or tube. If the wrench is to be used on a pipe of different diameter, the lining members 24 and 26 must be removed and replaced by similar members having a diiferent internal diameter adapted to fit the pipe to be gripped. Thus one wrench can be used on a number of different pipe sizes if corresponding sets of lining members are kept at hand. These lining members are removably held within the jaws l8 and 2%, by any suitable means such as lips 34, 3'5, 38 and 59, against which the straight edges of the lining members bear when the lining members are in place in the jaws. To hold these members against accidental disengagement from the jaws, any suitable detent such as a spring pressed ball 42 may be employed to press into a corresponding depression M in the outer surface of each lining member.

It is important that when the lining members are mounted in the jaws of the wrench, they have the same internal radius of curvature. Hence, to keep matched pairs of members together, one or more tie elements for each pair may be provided as shown. These tie elements may consist of wires in which span the clearance 32 and extend into holes :8 and 59 in opposing straight edge surfaces of the members on either side of the clearance 32. The holes 48 and 59 extend to points on the outer cylindrical surfaces of the members as at 52, the portions of the holes away from the flat faces being somewhat enlarged in diameter as indicated in Figure 4. Wires are thrust through tthe holes t3 and 50, then their end portions are flattened or otherwise distorted to prevent retraction of the ends through these holes. Thus the two liningmembers are permanently secured together in assembled relation but can move a limited distance toward and from each other since the wires fit loosely in the holes. Hence the wires do not interfere with the operation of the wrench when the lining members are mounted in the jaws of the wrench.

The jaw 20 has an ear 60 which is pivotally attached as at 62 to a toggle link 64, the latter being pivoted as at 66 to an extension 68 of the handle member I2 above the pivot M. The toggle link 64 is preferably made longitudinally adjustable so that its length can be increased or diminished as required to obtain the desired intensity of grip on a pipe when the handles are brought together as in Figure 1. The linkage is arranged as illustrated in Figure 1, so that when the handles and I2 are brought together to close the wrench, the toggle joint consisting of the extension 68 and the link 64 straightens out until the pivot axis 66 is in the line of centers of the pivot axes 52 and I4, or slightly beyond. The toggle action results in a powerful grip on the pipe clamped between the jaws l8 and 20.

For convenience in handling and holding the wrench, the handle 10 may be in the form of a channel, and the handle 12 may be a T-bar with the blade 69 adapted to enter the channel I0 when the handles are brought together. In order to open the wrench it is necessary to swing the handles I0 and I2 away from each other so as to break the toggle and rock the jaw about its pivot 22 away from the jaw l8. Since the operator ordinarily holds the wrench with one hand while using the other hand for some other purpose it is desirable that the wrench be capable of being opened without use of the second hand. For this purpose a trigger 10 may be mounted at the lower end of the handles, the trigger being mounted so that pressure of a finger of the operator thereon will serve to push one handle away from the other a sufiicient distance to break the toggle joint at 66. This trigger 10 shown in Figure 1 is pivotally attached to the handle I0 by a pin 12 which extends through the side walls of the channel. A portion of this trigger projects through a cutaway part of the bottom of the channel so as to be engageable by a finger of the operator. When the trigger is pressed toward the handle 12 it tends to push the handle 12 away from the handle [0 as illustrated in Figure 6, thus breaking the toggle and releasing the jaws from their grip on the pipe. A pin 14 in the handle member 10 riding in the slot 16 in the toggle member 10 limits the angle of swing as shown.

A modified form of trigger is shown at in Figure 7. This trigger may consist of a bent strip of metal pivoted as at 82 to the handle I0 and projecting down below the end of the handle. This projecting portion may be pressed by a finger to push the trigger against the handle I2 so as to swing the latter away from the handle [0 thus to open the wrench.

We claim:

1. A liner for the jaws of a pipe wrench, comprising two semi-cylindrical members arranged so that the straight edges of one member are respectively opposed to the straight edges of the other, each said member having a small hole extending from a straight edge face thereof to a point on the outer cylindrical surface thereof, and a tie element joining said members and extending loosely into said holes.

2. A liner for the jaws of a pipe wrench, comprising two semi-cylindrical members arranged so that the straight edges of one member are respectively opposed to the straight edge of the other, each said member having two small holes extending from a straight edge face thereof to points on the outer cylindrical surface of the member, the portion of each hol which is remote from the straight edge face being enlarged, two pieces of wire extending from respective holes in one said member into corresponding holes in the other said member, said wires each having enlarged ends disposed in the enlarged portions of the holes to connect said members loosely together.

EVO VERGNANI. STANLEY E. VERGNANI. MILTON H. VERGNANI.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 529,982 Wakefield Nov. 27, 1894 580,685 Hall Apr. 13, 1897 1,641,153 Butt Sept. 6, 1927 1,658,075 Butt Feb. '7, 1928 2,462,709 Ball Feb. 22, 1949 2,500,261 Parker Mar. 14, 1950 

